It is typical, in a variety of scientific endeavors, to employ test animals, and for various reasons, it is often necessary to control the food available to and consumed by the animals. This necessity occurs during, for example, research directed to the metabolic process and energy balance of an individual animal, the effectiveness and safety of medications, and nutrition physiology. It is a common practice to manually present the food to and remove it from the animal in order to control food availability. Such a manual procedure is clearly time consuming, expensive and unsuitable for long term tests which are often required in some of the experiments as described above.
It is known to use automatic feeders consisting of a plurality of fodder pans which are arranged on the periphery of a rotatable circular table. The table rotates at a uniform speed and the experimental animal has access, via a wire cage passage to a fodder pan as it passes from time to time in front of the wire cage passage. The time at which the food is available and the duration of the feed are controlled by the rotational speed of the circular table. Such a feeding apparatus requires the use of a special cage arrangement within the laboratory and is usually quite expensive. Moreover, the rotatable circular table device limits the area within the cage available for the animal's movement.
It is also known to use a feeding apparatus consisting of a tracked system on which fodder baskets are moved vertically on guide rails into and out of a series of cages. While the tracked system is useful when a plurality of aligned cages are used, individual feeding of the animals in selected cages is inhibited. Moreover, the tracked system requires the use of specially constructed cages which cooperate with the tracked fodder baskets.
It is, therefore, an object of this invention to provide an automatic or controllable feeding apparatus which is readily adaptable for use with a typical laboratory animal holding cage and which does not restrict the room available to the animal in the cage.
It is also an object of this invention to provide an apparatus, for the controlled feeding of laboratory test animals, which is economical to manufacture and maintain. The apparatus itself can be manually operated or it can be fully automatic when provided with the appropriate accessories.
It is still another object of this invention to provide a controllable feeding apparatus which substantially eliminates a danger common in the presently utilized automatic feeding devices, that is, the injuring of an animal during the presentation or removal of fodder baskets from the animal's cage.